* {
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    box-sizing: border-box;
  }
  
  html, body {
    margin: 0;
    padding: 0;
    height: 2000px;
    background-color: tomato;
  }
  
  #anchor {
    height: 360px;
    width: 100%;
    background-color: #F0F0F0;
  }
  
  .video {
    width: 640px;
    height: 360px;
    margin: 0 auto;
    background-color: black;
  }
  .video-fixed {
    position: fixed;
    top: 10px;
    left: 10px;
    width: 320px;
    height: 150px;
    cursor: all-scroll;
  }
  .video-fixed .masker {
    display: block;
  }
  .video-fixed:hover.masker {
   display: block;
   position: absolute;
   width: 100%;
   height: 180px;
   background-color: rgba(0, 0, 0, 0.8);
   z-index: 2;
 }